This manual covers Mercury-Mariner outboard engines manufactured between 1990 and 2000. It encompasses a wide range of two-stroke models, from 2.5 to 275 horsepower, including various cylinder configurations and specialized variants such as Optimax, EFI, Jet Drive, and XR6 Classic models. These engines are known for their robust engineering and reliable performance, making them a popular choice for a variety of marine applications. The purpose of this service repair manual is to provide comprehensive guidance for the maintenance, troubleshooting, service, and repair of your Mercury-Mariner outboard engine. It details every aspect of these operations, offering step-by-step procedures, technical specifications, and essential safety guidelines. With the inclusion of detailed illustrations and diagrams, this manual serves as an indispensable resource for owners, mechanics, and technicians seeking to ensure the optimal performance and longevity of their marine propulsion system.